pytype upgrade to 2018.12.21.
pytype upgrade to 2018.12.21.

anarkiwi/faucet,shivarammysore/faucet,gizmoguy/faucet,mwutzke/faucet,gizmoguy/faucet,faucetsdn/faucet,mwutzke/faucet,trungdtbk/faucet,REANNZ/faucet,trungdtbk/faucet,shivarammysore/faucet,faucetsdn/faucet,REANNZ/faucet,anarkiwi/faucet